Wire wrapper bit



June 1965 E. I. ALLEN 3,191,879

WIRE WRAPPER BIT Filed June 20, 1963 FIG 6 INVENTOR. EDWARD L. ALLEN 3o36 54 BY FIG. 5 MM AGENT United States Patent 3,191,879 WIRE WRAPPER BITEdward L. Allen, Ulster, Pa., assignor to Ingersoll-Rand Company, NewYork, N.Y., a corporation of New Jersey Filed June 20, 1963, Ser. No.289,178 Claims. (Cl. 242-7) This invention relates generally to wirewrapping tools and particularly to the improvements of bit arrangementstherefor and their operation.

The present invention is particularly adapted to wrapping fine gaugewire on electric terminals. It is common practice with wire wrapperswhich receive the free end of a wire to be wound, to provide springbiasing means for urging the wrapper bit toward a forwardmost positionas shown in US. Patent No. 3,028,107 granted April 3, 1962 to E. T.Hjorth. During a wire wrapping operation, the bit is urged against thespring progressively as the free end of the wire is withdrawn from thebit and wrapped to form the winding. While such an arrangement isnormally adequate, difficulty has been encountered in winding very smallgauge wires inasmuch as one wind or lap of the wire is urged back overthe preceding wind and causes bunching.

Accordingly, it is an object of this invention to provide a wirewrapping device which is particularly adapted to winding fine gaugewires.

Another object of this invention is to provide a wire wrapping devicehaving means for urging the bit thereof backwardly toward the toolprogressively during the wire wrapping operation an amount during eachturn equal to the gauge of each turn of wire.

Still another object of this invention is to provide the afore-mentioneddevice in which the rate of retraction of the bit is derived by firstuse thereof.

This invention contemplates a sleeve member immovably connected to awire wrapping tool, a bit member rotatable in the sleeve to wrap wireand having a head portion engaged by a biased keeper of the tool spindlefor rotation with the spindle and for urging the head portion forwardlyinto engagement with the sleeve member, a plug fixed to one of themembers extending outwardly therefrom toward the other member, and theother member threadedly engaging the plug to move the bit memberrearwardly when rotated, the other member having an axial slot throughthe threads for the plug to permit the keeper to move the bit axiallyforwardly in the sleeve until the head contacts the sleeve when thespindle is homed.

The foregoing and other objects and advantages will appear more fullyhereinafter from a consideration of the detailed description whichfollows, taken together with the accompanying drawings wherein severalembodiments of the invention are illustrated by way of example. It is tobe expressly understood, however, that the drawings are for illustrationpurposes only and are not to be construed as defining the limits of theinvention.

FIGURE 1 is a sectional view of the front end of a wire wrapping devicemade in accordance with the present invention,

FIGURE 2 is an enlarged sectional view taken on line 22 of FIGURE 1,

FIGURE 3 is an enlarged sectional view taken on line 3-3 of FIGURE 2illustrating the rear portion of the 3,191,879- Patented June 29, 1965novel bit positioned in its forwardmost position relative to the sleevethat surrounds it,

FIGURES 4 and 5 are sectional views similar to FIG- URE 3 illustratingthe novel bit and the sleeve that surrounds it in various other relativepositions, and

FIGURE 6 is a sectional view similar to FIGURE 3 illustrating a modifiedembodiment of the invention.

Referring now to the drawings and particularly to FIG- URE 1, only theforward end of the casing 10 is shown of a wire wrapping device or toolhaving a spindle 12 rotatable therein. The wire wrapping tool preferablyhas a homing arrangement (not shown), as an example as shown, described,and claimed in US. application 155,243 that was filed by I. A. Moore onNovember 22, 1961, now Patent No. 3,172,516, and assigned to the sameassignee as the present application. Homing, as above, is to beunderstood as automatically returning the spindle to the same angularrelationship in a tool after each wire wrapping operation. The forwardend of spindle 12 is hollow and slidably houses a recessed keeper member14 that is biased forwardly by a spring 16. A tubular clamp member 18extends from the front end of casing 10 and is locked in position by anut 20. A cam nut 22 is threadedly disposed on the forward end of thetubular clamp member 18, as will be further described.

A wire wrapper bit 30 is rotatably disposed in a tube or sleeve 50 andhas a head portion 32 abutting the rear end of the sleeve. Sleeve 50,with the bit 30, is inserted into the tubular clamp member 18 until thebit head 32 is engaged by the recessed keeper member 14. Cam nut 22 isthen threaded onto the member 18 urging its ends into clampingengagement with the sleeve 50. It will thus be seen that sleeve 50 isthen held against axial movement and rotation by the clamp member 18while the bit 30 is free to be rotated by the spindle 12 and to be movedaxially against or by the force of spring 16.

Bit 30 has an axial slot 34 at its rearward end adjacent its head 32which houses a plug or block 36, preferably of plastic or other suitablematerial. The forward end of bit 30 has an axial blind bore 42 toreceive an electrical terminal (not shown) and a peripheral slot 40 toreceive the free end of a wire (not shown) to be wrapped on the terminalin the blind bore 42. The rearward end of sleeve 50 has internal threads52 which engage the plug 36 and cut corresponding threads 38 thereonwhen the bit 30 is rotated. Internal threads 52 are to correspond insize to the fine wire to be wrapped, thus, with each wind of wire causedby a single rotation of the bit 30, the threads 52 and cut threads 38cause the bit 30 to move axially rearward a distance equal to the gaugeof the wrapped wire.

Sleeve 50 has an axial slot 54 that extends through the internal threads52 as shown in the drawings. Thus, when the wrapping operation iscompleted and the wire wrapping tool is stopped, the homing device (notshown) will align the plug 36 of bit 30 with the axial slot 54 of sleeve50. Spring 16 will then urge the recessed keeper member 14 and the bit30 axially forwardly to their starting or initial positions as shown inFIGURES 1 and 3. In practice, it has been found that the winds of wire,on a terminal being wrapped, tend to offset the forward bias of spring16. Thus, the speed of rotation of bit 30, when slot 54 is merelysufliciently wide to accommodate plug 36, will cause threads 38 to moveout of and into engagement with threads 52, as the plug crosses theslot, before spring 16 can move keeper 14 and bit 30 axially. Althoughspring biasing means to urge a wire wrapper bit forwardly is not new asshown in the afore-mentioned Hjorth patent and in my co-pendingapplication Serial No. 225,501 filed September 24, 1962 and assigned tothe same assignee as the present application, spring 16 has a secondfunction which is to take up backlash in the meshing threads 38 and 52which may be caused by continuous wear.

It should now be fully understood that the present invention provides awire wrapping bit and sleeve arrangement which provides means fordriving the bit rearward- 1y with each turn, a distance equal to asingle turn of a fine wire being wrapped, that has automatic returnmeans when the tool is stopped and horned for returning the bit to itsstarting position. While the preferred embodiment of the invention is asshown, the plug 36 could be housed in the rearward end of sleeve 30 withthe threads 52 and the axial slot 54 then being disposed at the rearwardend of bit 30 adjacent the head 32.

Toward this end, as shown in FIGURE 6, a modified bit 30a and sleeve 50aare provided corresponding to bit 30 and sleeve 50. In this instance,sleeve 50a has a slot 34a, corresponding to slot 34, in its rearward endfor retaining a plug 36a, corresponding to plug 36, against movement.Bit 30a has threads 52a, corresponding to threads 52, adjacent its head32a corresponding to head 32. Bit 30a also has an axial slot 54a,corresponding to slot 54, which extends through threads 52a.

Althought several embodiments but a single embodiment of the inventionhave been illustrated and described in detail, it is expresslyunderstood that the invention is not limited thereto. Various changesmay be made in the design and arrangement of the parts without departingfrom the spirit and scope of the invention as the same will now beunderstood by those skilled in the art.

I claim:

1. In combination with a wire wrapping tool having a rotatable spindlewith a forwardly biased keeper:

(a) a sleeve member connected at its rearward end to the tool and heldimmovable thereby;

(b) a bit member rotatably disposed in said sleeve member and having ahead portion at its rearward end engaged by said keeper to rotate thebit member when the spindle rotates and to urge the head portion axiallyforwardly into engagement with the rearward end of the sleeve member;

(c) a plug fixedly connected to one of said members extending outwardlytherefrom toward the other of said members;

(d) the other of said members having threads at its rearward endengaging the plug to form threads thereon and providing a threadedconnection between the two members for moving the bit member rearwardlywhen said bit member is rotated to wind a wire; and

(e) the other of said members having an axial slot through the threadsthereof to permit axial movement of the plug alined therewith when thespindle is stopped from rotating and the keeper urges the bit memberforwardly until the head portion engages the sleeve member.

2. In combination with a wire wrapping tool having a rotatable spindlewith a forwardly biased keeper:

(a) a sleeve member connected at its rearward end to the tool and heldimmovable thereby;

(b) a bit member rotatably disposed in said sleeve member and having ahead portion at its rearward end engaged by said keeper to rotate thebit member when the spindle rotates and to urge the head portion axiallyforwardly into engagement with the rearward end of the sleeve member;

(c) a plug fixedly connected to one of said members 4 extendingoutwardly therefrom toward the other of said members;

(d) the other of said members having threads engaging the plug andforming meshing threads thereon cooperating to move the bit memberrearwardly when said bit member is rotated to wind wire; and

(e) the other of said members having an axial slot through the threadsthereof to permit axial movement of the plug alined therewith when thespindle is stopped from rotating and the keeper urges the bit memberforwardly until the head portion engages the sleeve member.

3. In combination with a wire wrapping tool having a rotatable spindlewith a forwardly biased keeper:

(a) a sleeve member immovably connected to the tool and having an axialslot in the rearward end of its inner wall;

(b) a bit member rotatably disposed in said sleeve member and having ahead portion at its rearward end engaged by said keeper to rotate thebit member when the spindle rotates and to urge the head portion axiallyforwardly into engagement with the rearward end of the sleeve member;

(c) the bit member having an axial slot extending forwardly from thehead portion;

(d) a plug fixedly held in the axial slot of one of the members andextending therefrom toward the other of the members;

(e) the other of said members having threads, interrupted by the axialslot thereof, engaging the plug and forming meshing threads thereoncooperating to move the bit member rearwardly when said bit member isrotated to wind wire; and

(f) the plug being movable axially through the slot interrupting thethreads of the other member when alined therewith and when the spindleis stopped from rotating and the keeper urges the bit member forwardlyuntil the head portion engages the sleeve member.

4. In combination with a wire wrapping tool having a rotatable spindlewith a forwardly biased keeper:

(a) a sleeve immovably connected to the tool and having internallydisposed threads at its rearward end and an axial slot through thethreads;

(b) a bit rotatably disposed in said sleeve and having a head portion atits rearward end engaged by said keeper to rotate the bit when thespindle rotates and to urge the head portion axially forwardly intoengagement with the rearward end of the sleeve;

(0) the bit having an axial slot extending forwardly from the headportion;

(d) a plug fixedly held in the axial slot of the bit extending outwardlytherefrom toward the sleeve; (e) the threads of the sleeve engaging theplug and forming meshing threads thereon cooperating to move the bitrearwardly when said bit member is rotated to wind wire; and

(f) the plug being movable axially in the slot in the sleeve through thethreads when alined therewith and when the spindle is stopped fromrotating to permit the keeper to urge the bit forwardly in the sleeveuntil the head portion engages the rearward end of the sleeve.

5. In combination with a wire wrapping tool having a rotatable spindlewith a forwardly biased keeper:

(a) a sleeve immovably connected to the tool and having an internallydisposed axial slot at its rearward end;

(b) a bit rotatably disposed in said sleeve and having a head portion atits rearward end engaged by said keeper to rotate thebit when thespindle rotates and to urge the head portion axially forwardly intoengagement with the rearward end of the sleeve;

(0) the bit having threads extending forwardly from 5 6 I the headportion and an axial slot through the References Cited by the Examinerthreads; UNITED STATES PATENTS (d) a plug fixedly held in the axial slotof the sleeve extending outwardly therefrom toward the bit; g l (e) thethreads of the bit engaging the plug and form- 5 6 a 2,940,687 6/60Mason 242-1582 mg meshing threads thereon cooperating to move h d1 h tatd t d 3,028,107 4/62 Hjorth 242-7 t f f a Y en 1 m Wm 3,098,615 7/63Bach et a1 242 -7 (f) the plug being movable axially in the slot in theFQREIGN P ENTS bit through the threads when alined therewith to per- 1035 05 1 1 Great i i mit the keeper to urge the bit forwardly in thesleeve until the head portion engages the rearward end of MERVIN STEINPnmary Examiner the sleeve when said bit is stopped from rotating.RUSSELL C. MADER, Examiner.

1. IN COMBINATION WITH A WIRE WRAPPING TOOL HAVING A ROTATABLE SPINDLEWITH A FORWARDLY BIASED KEEPER: (A) A SLEEVE MEMBER CONNECTED AT ITSREARWARD END TO THE TOOL AND HELD IMMOVABLE THEREBY; (B) A BIT MEMBERROTATABLY DISPOSED IN SAID SLEEVE MEMBER AND HAVING A HEAD PORTION ATITS REARWARD END ENGAGED BY SAID KEEPER TO ROTATE THE BIT MEMBER WHENTHE SPINDLE ROTATES AND TO URGE THE HEAD PORTION AXIALLY FORWARDLY INTOENGAGEMENT WITH THE REARWARD END OF THE SLEEVE MEMBER; !C) A PLUGFIXEDLY CONNECTED TO ONE OF SAID MEMBER EXTENDING OUTWARDLY THEREFROMTOWARD THE OTHER OF SAID MEMBERS; (D) THE OTHER OF SAID MEMBERS HAVINGTHREADS AT ITS REARWARD END ENGAGING THE PLUG TO FORM THREADS THEREONAND PROVIDING A THREADED CONNECTION BETWEEN THE TWO MEMBERS FOR MOVINGTHE BIT MEMBER REARWARDLY WHEN SAID BIT MEMBER IS ROTATED TO WIND AWIRE; AND (E) THE OTHER OF SAID MEMBERS HAVING AN AXIAL SLOT THROUGH THETHREADS THEREOF TO PERMIT AXIAL MOVEMENT OF THE PLUG ALINED THEREWITHWHEN THE SPINDLE IS STOPPED FROM ROTATING AND THE KEEPER URGES THE BITMEMBER FORWARDLY UNTIL THE HEAD PORTION ENGAGES THE SLEEVE MEMBER.